The present invention relates to a payoff device for use with a reeless package such as a reeless wire or cable coil which is particularly well suited for mounting on a utility truck such that a reeless package of material may be easily, conveniently, and safely unwound in the field.
Devices for insertion into the hollow core of a roll or coil of material to support the roll or coil and to facilitate unwinding are known. It is also known in the art to use an adjustable device to facilitate initial insertion into a roll core prior to clamping expansion or to accommodate rolls or coils with different inside diameters through various degrees of expansion. There is also known in the art expandable and collapsible holders about which material is wrapped while the holder is in an expanded state. Examples of expandable and collapsible holders or mandrels can be found, for instance, in U.S. Pat. Nos.: 1,466,153; 2,682,924; 2,762,577; 3,918,659; 4,124,171; 4,278,112; 4,763,850; 4,995,569; and 5,318,236.
There is also know in the art support stands for use in the dispensing or holding of wound material as represented by U.S. Pat. Nos. 1,807,549; 3,918,659 and 5,810,283.
Rolls of electrical wire or cable such as those used in the field by electric utilities and the like for installation and repair often are relatively heavy (e.g., 1,500 lbs) and can be cumbersome to handle and payoff. These rolls of wire or cable used by utility companies in the field are wound onto wooden reels and typically there is a frame mounted in the truck bed of the utility vehicle for supporting the wooden reel. The wire or cable wrapped on the wooden reel is then transported in the field for unwinding by pulling on an end of the wire thereby rotating the reel on which it is wound. The extra weight and material associated with the wooden reel with rolled material introduces added production and shipping costs for the manufacturer of the rolls as well as handling and disposal costs for the utility company or the like dispensing the rolled material. The wooden reels also take up a lot of room in the truck bed thus limiting space which could be put to other use such as providing additional storage space for coil material or tooling to prolong the time out in the field. Furthermore, the use of such wooden reels is detrimental to the environment by causing trees to be consumed and taking up space in landfills after their useful life.
In addition, under current practice reels are mounted in trucks on support frames that are not multi-positional with respect to the supporting truck bed (e.g support frameworks that are non-rotatable about a vertical axis). For example, many prior art support frames have two spaced apart support structures each rigidly secured to the bed of the truck for supporting opposite ends of a shaft about which the reel or spool is rotated during payoff. This arrangement makes the device ill suited for any repositioning of the support structure. Thus, a worker in the field must reposition the entire truck in order to adjust the direction of payoff. This can be very difficult if there are obstacles which hinder the movement of the truck and can be dangerous if it forces a truck into an unstable position or in a position which interferes with others, such as by blocking street traffic. There also arises situations wherein it would be beneficial to be able to provide for loading of new cable or wire or the like in a certain orientation which is not possible in non-adjustable prior art reel support frame structures.
There is need in the art for a reeless package payoff device which is durable, not overly complex (but yet highly versatile), safe and easy to both load and operate in a dispensing mode and which is well suited for use in the field such as on the back of a utility truck or the like or on a transported trailer.
According to the present invention, there is provided a reeless package payoff device and method of operation of the same which avoids many of the limitations of the prior art devices in providing a highly versatile and easy to operate system that is well suited for field use such as on the back of utility vehicles or the like. Preferably the reeless package payoff device comprises a clamp assembly that is supported by a main shaft rotatably mounted in bearings of a support frame structure such that the clamp assembly and shaft rotate together. A preferred arrangement features a main shaft which is supported on one of its ends by bearings that are spaced apart along the end portion of the shaft to a sufficient extent based on the anticipated loads. The support frame structure that supports the main shaft is preferably, itself, multi-positionable to provide for different payout orientations such as by way of an upper support framework portion that pivots with respect to a non-rotatable lower portion. The support frame is attached to the bed of a utility truck or other vehicle, preferably by way of releasable attachment means which securely fastens the lower portion of the support frame to the bed or the truck or other suitable underlying support and provides for removal of the support structure from the underlying support when not required or in use.
The clamp assembly preferably comprises first and second hubs axially spaced along the main shaft. Each hub is connected so as to rotate together with the main shaft with a preferred embodiment featuring a fixed hub and an axially mobile hub with the latter being keyed to the main shaft so as to rotate therewith, but free to axially adjust along the main shaft by way of a key/slot arrangement. The clamp assembly further comprises clamp pads (e.g., 4) that are driven radially in and out by an expansion/contraction device such as a plurality of scissor linkage assemblies to which the clamp pads are respectively attached. The scissor linkage assemblies feature scissors linkage that are pivotably attached at their radial outer end to a support structure of the clamp pads, are pivotably joined together at an intermediate area and are further pivotably attached at respective radial interior ends to the axially spaced apart mobile hub and fixed hub. The mobile hub is moveable axially such that, upon movement toward the fixed hub, it causes the scissors linkage to move the clamp pads radially outward into compressive attachment contact with the interior surface of a reeless package placed on the clamp assembly. Alternatively, the clamp assembly may have clamp pads attached to fixed arms. Such an arrangement allows rotation with a variable ID with the variation limited mainly by the escentricity of the coil or roll package. The advantages of this are that no manual lifting of the coil is required, less torque is needed, there is no movement of the arms circumferencially inside the coil, thereby preventing damage to the coil by scraping, marring, etc., and there is less wear on pivot parts. When it is desired to remove a reeless package or replace a completely paid out reeless package, the previously expanded clamp assembly can be collapsed in a controlled fashion to a suitable state to receive a replacement reeless package having a similar or smaller sized interior diameter. Alternatively, if the replacement reeless package has a larger interior diameter than the previous reeless package and the prior reeless package was completely paid out, then the replacement package can be simply inserted over the earlier expanded clamp pads and the clamp pads further moved radial out by moving the mobile hub even closer to the fixed hub until the replacement reeless package is fixed with respect to the clamp pads. Thus, the above described preferred embodiment of the clamp assembly of the present invention can quickly and accurately conform to a variety of different diameter reeless packages which was not the case with the non-adjustable wooden reel support payoff devices in the prior art. In addition, while the clamp pad assembly is designed for use with reeless packages, the clamp pad assembly of the present invention is versatile enough to handle rolls or coils of material which do have an internal reel or spool or the like, although for the reasons outline above such as weight and volume reduction, reeless packages are preferred for use with the present invention.
The mobile hub is driven or moved axially along the main shaft by a drive assembly which in a preferred embodiment features a driver such as a drive screw threadedly connected to the mobile hub. The drive screw preferably has a central through hole which receives a smaller diameter end extension of the main shaft with the drive screw being held in place axially by a locking collar attached to the free end of the main shaft""s smaller diameter end extension and the stepped shoulder of the main shaft leading to the smaller diameter end extension. The drive screw is thus axially retained by the locking collar and stepped shoulder, but free to rotate about the main shaft""s smaller diameter end extension with the assistance of a thrust bearing provided axially inward of the locking collar. With this arrangement, the mobile hub is also preferably formed as a cylindrical sleeve with a sufficient diameter to receive and axially slide along the larger diameter portion of the main shaft extending to the stepped shoulder. In a preferred embodiment, the sleeve of the mobile hub is provided with interior threads for engagement with the drive screw""s external threads such that, upon rotation of the drive screw, the mobile hub is moved axially along the main shaft either closer to or away from the fixed hub depending on the direction of rotation of the drive screw and the clamp assembly is correspondingly expanded or contracted.
The key/slot connection between the mobile hub and main shaft allows for the axial movement imparted by the drive screw on the mobile hub, while allowing for the mobile hub and main shaft to rotate as a unit in similar fashion to the fixed hub and main shaft combination.
The reeless package (reference will be made to xe2x80x9ccoilxe2x80x9d hereafter for simplicity, but a variety of packages of wound material are suited for use with the clamp assembly of the present invention) is held in place side to side by a fixed end plate and a removable end plate. During loading of the coil, the removable end plate is removed from its coil retention position and a coil of electrical wire, for example, is placed on the clamp assembly. The removable end plate is attachable to the drive screw through locking clamps such that the removable end plate can be rotated by an operator to drive the drive screw. The removable end plate is thus used to drive the drive screw such that the mobile hub is axially moved along the main shaft to cause the clamp pads to come in contact and retain in position the interior surface of the coil. The removable end plate is then moved against the side of the coil and locked into place. An optional locking collar includes a sleeve with staggered holes that is rotated around the drive screw until a hole in the sleeve aligns with a hole in the drive screw. A locking pin is inserted through the sleeve hole and the shaft hole to lock the removable end plate in place. The locking pin may also include a cotter pin or similar safety device to prevent accidental removal of the locking pin. In a preferred embodiment, the locking clamps are designed to be relatively easily released by an operator such that the removable end plate can be shifted from its clamped attachment position on the drive screw (e.g., an enlarged outer end portion of the drive screw) to a clamped attachment position on the mobile hub""s (e.g., an exterior portion of the mobile hub having a similar diameter as the enlarged outer end portion of the drive screw). Also, the clamp pads supported on the clamp assembly have an axial length suited for contact and retention of a wide variety of different width reeless packages and to provide for end-to-end clamping of both relatively small width and large width packages. This versatility in full support of different width coils is facilitated by having the end plates provided with radially interior, circumferentially spaced slots that are sized to axially receive therethrough the ends of the clamp pads and also to allow for a full range of expansion and contraction in the radial direction.
The device is also equipped with a manually adjustable brake and a stop pin to orient and prevent rotation of the clamp assembly during loading and clamping. There is also provided a locating pin to prevent rotation of the upper portion of the support frame when the locating pin is inserted through the upper portion and within one of a plurality of circumferentially spaced pin reception holes in a lower portion of the support frame about which the upper portion rotates and preferably is supported by. Thus, with the clamp assembly lock pin and pivoting support locating pin in position, the loading and clamping operations can be performed without undesired rotation of either the clamp assembly or support frame. This also provides locking for transport while the coil is on the truck and for payoff of the coil. Following loading of the coil and positioning of the end plate in its coil retention position, the clamp assembly lock pin is released and the brake (e.g., a spring applied caliper brake) is set (or pre-set) to a desired state to allow for drag adjustment as needed to minimize over spinning following a pay out of material. The clamp assembly brake contact member is an annular ring attached by a plurality of circumferentially spaced bolt sleeves to the hub region of the fixed end plate with at least one hole circumferentially spaced for reception of the clamp assembly locking pin.
The locating pin may also be removed at any desired time so the clamp assembly can be rotated to a desired payoff direction or to a desired coil loading position.
With the foregoing and other advantages and features of the invention that will become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following brief description of the drawings, the detailed description of the invention, the appended claims and to the several views illustrated in the attached drawings